Not Applicable
Appendix A xe2x80x9cData Acquisition Programxe2x80x9d and Appendix B xe2x80x9cSeed Mapping Programxe2x80x9d referenced herein are contained in the enclosed compact disc in a file entitled xe2x80x9cUC2000-174-1.txtxe2x80x9d created on Jun. 4, 2001 and having a 24 kb file size. The computer program code, which exceeds 300 lines, is submitted on compact disc in accordance with 37 CFR 1.52. Two compact discs are provided according to 37 CFR 1.52(e)(4). Appendix A and Appendix B contained on the compact disc are incorporated by reference herein.
1. Field of the Invention
This invention pertains generally to precision farming methods, and more particularly to ultra-precise (i.e., centimeter accuracy), Global Positioning System (GPS) based mapping of seeds and vegetation while dispensed from a planter for site-specific cultivation and plant specific chemical application.
2. Description of the Background Art
Successful agricultural enterprises seek to optimize crop production while minimizing the input costs of applying herbicides and fertilizers and other activities thereby maximizing the profits realized from a particular crop. It is common practice for the typical farmer to apply pesticides or fertilizers uniformly throughout the field even though less than 50% of land area is covered by the target foliage. Precision farming techniques such as yield monitoring, variable rate applications, crop and soil property sensing etc. can allow a reduction in the application of chemical pesticides and fertilizers by delivering the chemical to the crop plant rather than the entire field. The annual application of pesticides and fertilizers by agriculturalists in the United States alone is substantial. For example in 1989, over 800 million pounds of pesticides were used in US agriculture. Accordingly, targeted spray can lead to a huge reduction of chemical input into US agriculture. This approach not only reduces the cost of chemicals, but also reduces the pesticide load on the environment, particularly on ground water and streams. Such precision techniques have had limited success because they are often man-power intensive to assure accuracy.
One of the key elements that aided the development of precision farming techniques is the ability to xe2x80x9caccuratelyxe2x80x9d determine the locations within a field using GPS technology. Sub-meter accuracy offered by early GPS systems that utilized differential corrections (DGPS), has been satisfactory for many precision farming applications where sub-meter accuracy is acceptable.
The recent development of real-time kinematics (RTK) based GPS systems have made it possible to determine field positions with an accuracy of 1 centimeter. The application of this technology to agriculture can have tremendous economic and environmental benefits. The centimeter accuracy of the RTK based GPS technology allows the movement from site-specific precision farming with sub-meter accuracy to plant-specific ultra-precision farming with centimeter accuracy.
Many different types of autonomous systems have been attempted for use with agricultural vehicles. One system used radio frequency to guide a tractor with an accuracy of 1 less than 5 centimeters. Another utilized a laser guidance system to achieve an accuracy of less than 6 millimeters. Image analysis systems using a video camera have also been developed, some reporting accuracy of around 7 millimeters at low weed loads and 12 millimeters at high weed loads with permitted speeds up to 16 kilometers per hour. Other imaging based systems utilize a color vision system to discriminate between plants and weeds to allow differential spraying. However, since optical discrimination between plants and weeds using image analysis to extract relevant features is computationally intensive, these systems must employ very low ground speed. Mechanical systems have also been developed using a leader cable system for reliable tractor guidance or implemented a mechanical contact type guidance system for use in green houses. Other systems use a combination of ultrasonic and dead reckoning to guide a tractor. Finally, other precision farming systems have used RTK GPS for vehicle guidance because of its technical superiority and economic advantages compared to all other systems.
Accordingly, a need exists for accurate and inexpensive precision farming techniques that can efficiently identify the location of seeds and plants within a field for selective application of pesticides and fertilizers and tilling without causing operator fatigue or having large man-power requirements. The present invention satisfies that need, as well as others, and generally overcomes the deficiencies found in existing equipment.
The present invention is a method and system for generating a centimeter accuracy map of the location of seeds or vegetation as they are planted from an agricultural planting machine.
By way of example, and not of limitation, in accordance with an embodiment of the invention a planting machine such as a Salvo 650 vacuum planter, is fitted with a centimeter accuracy RTK GPS receiver feeding a data logger, and optical sensors are placed adjacent the planter shoes to detect seeds as they fall through the seed tubes. Alternatively, micro-switches or other sensors could be used to sense transplants as they are planted. The data logger monitors GPS time and UTM coordinates, as well as the optical sensors. Ground speed and azimuth can also be monitored. The seeds are time-tagged as they fall through the seed tubes, and software is used to process the seed dispensing time and GPS location data and estimate the exact coordinates of each seed and its distance from adjacent seeds. This information is then used to generate a planting map. It should be recognized, however, that it is not necessary to use centimeter accuracy RTK GPS for time tagging seeds as they are planted. Any centimeter accuracy GPS could be used, and data may be post-processed to generate a planting map.
In accordance with another embodiment of the invention, the sensors are omitted. Instead of sensing seeds falling through the seed tubes, the invention controls the seed dispensing operation. In this embodiment of the invention, RTK GPS is used to determine when the seed dispenser is above the desired planting location. When the desired location has been reached, the invention activates the seed dispenser to drop the seed. This can be accomplished by, for example, cutting off the vacuum on a vacuum metering plate commonly used in vacuum planters. By dropping the seeds at the desired location in this manner, check row planting is made possible. The planting map generated in this embodiment is essentially the same as before, except that the invention determines the locations for seeds rather than senses the locations for the seeds.
Once the planting map is generated, the map can then be used for a variety of purposes such as applying pesticides directly to the plants, cultivating, plant thinning, and other field operations. In addition, by further employing a greenness sensor to detect green plants and identify those plants (e.g., weeds) which are not a part of the original seed/plant map, chemical or non-chemical (such as biological) herbicides can be selectively applied to control weeds. Additionally, mechanical cultivation, pulsed electrical shock, and flame weeding is also made possible on an automated basis. Vegetative mass where plants are not expected on the plant map can be cultivated or otherwise destroyed. Further, seed application can be controlled during planting.
Thus, it can be seen that accuracy in seed placement makes it possible to develop an accurate seed map that can be used to target chemical application and/or mechanical cultivation thus reducing the cost of production and protecting the environment. Moreover, such seed maps can assist in autonomous vehicle guidance, which can reduce operator fatigue as well as improve machinery performance by reducing overlap during field operations such as tillage, chemical application, etc.
An object of the invention is to provide a system for identifying accurate plant locations using global positioning system data and creating a virtual plant map.
Another object of the invention is to provide a method for seed mapping using centimeter accuracy global positioning system.
Another object of the invention is to provide a system that reduces the amount of fertilizers and pesticides and the like that is applied to a field by permitting plant and location specific applications.
Further objects and advantages of the invention will be brought out in the following portions of the specification, wherein the detailed description is for the purpose of fully disclosing preferred embodiments of the invention without placing limitations thereon.